Tunnel kilns

ABSTRACT

A tunnel kiln includes a suspended roof which is spaced at each longitudinal edge from the sidewalls, the intermediate space is filled with a series of refractory bricks each of which is profiled so that its lower surface lies close to the upper surface of an unladen part of the ceramic ware trolley of the kiln.

United States atent Inventor Gregor Buschermohle lhbenburn, Germany Appl. No. 841,699 Filed July 15, 1969 Patented Feb. 2, 1971 Assignee Keller Ofenbau Gmbll Laggenheck Westfalia, Germany ajoint stock company Priority Sept. 5, 1968 Germany 1,758,940

TUNNEL KILNS 4 Claims, 2 Drawing Figs.

U.S. Cl 263/28, 25/142; 263/46 Int. Cl F271) 9/00 [50] Field of Search 263/28, 46; 25/142B, 1420; 34/242 [56] References Cited UNITED STATES PATENTS 1,738,580 12/ l 924 Himmelright 263/46 2,013,905 9/1935 Adams, Jr 263/46X 2,676,793 4/1954 Jones 263/46X Primary Examiner-John J. Camby A ttorney- Mason, Mason and Albright ABSTRACT: A tunnel kiln includes a suspended roof which is spaced at each longitudinal edge from the sidewalls, the intermediate space is filled with a series of refractory bricks each of which is profiled so that its lower surface lies close to the upper surface of an unladen part of the ceramic ware trolley of the kiln.

TUNNEL KILNS BACKGROUND OF THE INVENTION Field of the Invention This invention relates to a flat firing tunnel kiln for ceramic ware. particularly bricks. with a roof preferably of the suspended type so supported in relation to the two longitudinal sides of the kiln as to leave a space, in the transverse direction, between each of the long sides and the roof.

An object of the invention is to provide a kiln in which the frame of the firing trolley and seals of the kiln are afforded a high degree of protection against heat radiation, to prevent damage thereto.

SUMMARY OF THE INVENTION According to the present invention there is provided in a tunnel kiln for ceramic ware, a roof structure, two longitudinally extending sidewalls both of which are spaced from respective side edges of the roof structure, at least one refractory brick bridging the space between the roof and one sidewall, at least one refractory brick bridging the space between the roof and the other sidewall, and a trolley having an upper surface, said trolley being capable of carrying ceramic ware through the kiln, each said bridging brick having a lower surface which is closely spaced from an unladen portion of the upper surface of the trolley whereby flow of high-temperature gases through the space between the roof structure and the sidewalls is restricted.

BRIEF DESCRIPTION OF THE DRAWINGS Two specific examples of a flat firing kiln in accordance with the invention will now be described, by way of example, with reference to the accompanying purely diagrammatic drawings, in which:

FIG. I is a cross section through a portion of one embodiment of a flat firing kiln in accordance with the invention; and

FIG. 2 is a cross section through a portion of a second embodiment of a flat firing kiln in accordance with the invention.

The flat firing tunnel kiln can accommodate a firing trolley 3, which is moved through the firing chamber 2 of the kiln.

By way of ware to be fired, the firing trolley 3 carries flat objects 4, for example, bricks. Above the ware to be fired is a suspended roof 5, the connection of which to the kiln wall 6 consists of a side or bridging brick 7 or 8, made of a refractory material. A projection 7a or 8a, on this side brick 7 or 8 rests on a part of the suspended roof, while a channel 9, in the longitudinal sidewall 6 of the kiln, supports the other end 7h or 8b, of the side brick 7 or 8.

The side brick 7 or 8 may be rectangular in shape, or it may be profiled to other shapes and provided with a shoulder on the side that faces towards the firing trolley.

The side brick 7 or 8 is so arranged that only a small gap 10 or I I lies between the lower horizontal surface thereof and the unladen part of the upper surface of the trolley 3. The effect of this is that the lower structure of the firing trolley 3 and a side seal 12 of the kiln are protected from the high temperature kiln atmosphere, so that these parts cannot be damaged.

In the first embodiment the lower horizontal face of the brick 7, whereas the lower horizontal face of the brick 8 of the second embodiment has a longitudinally extending ridge 13 along the edge thereof remote from the longitudinal sidewall. The ridge 13 extends into a groove 14 formed in the upper surface of the trolley 3 thus forming an additional restriction to the sideways flow of hot kiln gases.

1 claim:

1. In a tunnel kiln for ceramic ware:

a roof structure;

two longitudinally extending sidewalls both of which are spaced from respective side edges of the structure;

at least one refractory brick bridging the space between the roof and one sidewall; a trolley having an upper surface, said trolley being capable of carrying ceramic ware through the kiln; and

each said bridging brick having a lower surface which is closely spaced from an unladen portion of the upper surface of the trolley whereby flow of high-temperature gases through the space between the roof structure and the sidewalls is restricted.

2. A kiln according to claim 1, wherein each bridging brick is supported by the roof structure and by the corresponding longitudinal wall.

3. A kiln according to claim 2, wherein the roof structure has upwardly facing surfaces and each longitudinal sidewall has a corresponding upwardly facing surface, each said bridging brick being supported at lateral edge surfaces thereof, by said upwardly facing surfaces of the roof structure and of the sidewalls.

4. A kiln according to claim I, wherein the lower surface of each bridging brick has a longitudinally extending, downwardly projecting ridge and the upper surface of the trolley has a longitudinally extending groove, said ridge extending into said groove. 

1. In a tunnel kiln for ceramic ware: a roof structure; two longitudinally extending sidewalls both of which are spaced from respective side edges of the structure; at least one refractory brick bridging the space between the roof and one sidewall; a trolley having an upper surface, said trolley being capable of carrying ceramic ware through the kiln; and each said bridging brick having a lower surface which is closely spaced from an unladen portion of the upper surface of the trolley whereby flow of high-temperature gases through the space between the roof structure and the sidewalls is restricted.
 2. A kiln according to claim 1, wherein each bridging brick is supported by the roof structure and by the corresponding longitudinal wall.
 3. A kiln according to claim 2, wherein the roof structure has upwardly facing surfaces and each longitudinal sidewall has a corresponding upwardly facing surface, each said bridging brick being supported at lateral edge surfaces thereof, by said upwardly facing surfaces of the roof structure and of the sidewalls.
 4. A kiln according to claim 1, wherein the lower surface of each bridging brick has a longitudinally extending, downwardly projecting ridge and the upper surface of the trolley has a longitudinally extending groove, said ridge extending into said groove. 